Meine Merkliste  

Water content variation of p-n-heptylphenol reference material

Water content variation of candidate p-n-heptylphenol (HP) reference material (ampoule form) for preparation of a primary standard solution based on the Japan Calibration Service System, a national standards dissemination system, under the Measurement Law of Japan, was examined by a Karl-Fischer water content meter. As prepared samples, liquid-phase HP and upper, middle, and lower layers of solid-phase HP were measured since characteristic phase transition occurs near room temperature (melting point: 28.98 °C). As a result of water content in liquid- and solid-phase HP, water content variation among three layers of solid-phase is found in within ampoules, though water content variation of liquid-phase is not found. Between-ampoule variation of water content is also found using total ampoules of liquid-phase HP used to eliminate within-ampoule variation. Moreover, water content variation is secondarily confirmed by the results of the amount-of-substance fraction of HP based on a differential scanning calorimeter. From these results in this study, it is concluded that within- and between-ampoule variations of water content may depend on phase transition and water loss during ampouling of candidate reference material, respectively.

Autoren:   Nobuyasu Hanari, Ryoko Iwasawa, Satoko Otsuka, Naomi Fujiki, Ayako Matsumoto, Toshihide Ihara, Keiichiro Ishikawa, Takashi Yarita
Journal:   Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement
Jahrgang:   2010
DOI:   10.1007/s00769-010-0714-5
Erscheinungsdatum:   20.11.2010
Mehr über Springer-Verlag
Ihr Bowser ist nicht aktuell. Microsoft Internet Explorer 6.0 unterstützt einige Funktionen auf Chemie.DE nicht.